# Python | Solve given list containing numbers and arithmetic operators

Given a list containing numbers and arithmetic operators, the task is to solve the list.

Example:

```Input: lst =  [2, '+', 22, '+', 55, '+', 4]
Output: 83

Input: lst =  [12, '+', 8, '-', 5]
Output: 15
```

Below are some ways to achieve the above tasks.

Method #1: Using Iteration
We can use iteration as the simplest approach to solve the list with importing different operators.

 `# Python code to solve the list ` `# containing numbers and arithmetic operators ` ` `  `# Importing ` `from` `operator ``import` `add, sub ` ` `  `# Function to solve list ` `def` `find(``Input``): ` `    ``ans ``=` `0` `    ``options ``=` `{``'+'``: add, ``'-'``: sub} ` `    ``option ``=` `add  ` `    ``for` `item ``in` `Input``: ` `        ``if` `item ``in` `options: ` `            ``option ``=` `options[item] ` `        ``else``: ` `            ``number ``=` `float``(item) ` `            ``ans ``=` `option(ans, number) ` `    ``return` `ans ` ` `  `# Input Initialization ` `lst ``=` `[``91``, ``'+'``, ``132``, ``'-'``, ``156``, ``'+'``, ``4``] ` ` `  `# Calling function ` `Output ``=` `find(lst) ` ` `  `# Printing output ` `print``(``"Initial list"``, lst) ` `print``(``"Answer after solving list is:"``, Output) `

Output:

```Initial list [91, '+', 132, '-', 156, '+', 4]
Answer after solving list is: 71.0
```

Method #2: Using eval and join

 `# Python code to solve the list ` `# containing numbers and arithmetic operators ` ` `  `# Input list initialization ` `lst ``=`  `[``2``, ``'+'``, ``22``, ``'+'``, ``55``, ``'+'``, ``4``] ` ` `  `# Using eval and join ` `Output ``=` `eval``(``' '``.join(``str``(x) ``for` `x ``in` `lst)) ` ` `  `# Printing output ` `print``(``"Initial list"``, lst) ` `print``(``"Answer after solving list is:"``, Output) `

Output:

```Initial list [2, '+', 22, '+', 55, '+', 4]
Answer after solving list is: 83
```

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